Mechanical governor for internalcombustion engines



W. E. ARMSTRONG 2,382,952

Aug. 21, 1945.

' MECHANICAL GOVERNOR FOR INTERNAL-COMBUSTION ENGINES 5 Sheets-Sheet 1Filed Dec. 25, i945 A ug. 2l, 1945. w. E. ARMSTRNG 2,382,952.

MECHANICAL GOVERNOR FOR INTERNAL-COMBUSTION ENGINES Filed Dec. 25, 19435 sheets-sheet 2 WMQ/ MJPMPEAm/simnq Aug. 21,-1945. w E. ARMSTRONG2,382,952

MECHANICAL GOVERNOR FOR` INTERNAL-COMBUSTION ENGINES Filed Dec. 23, 19453 Sheets-Sheet 5 E E E Patented Aug. 21, 1945 MECHANICAL GOVERNOR FORINTERNAL- COMBUSTION ENGINES Werner E. Armstrong, Milwaukee, Wis.,assignor to Briggs & Stratton Corporation, Milwaukee, Wis.. acorporation of Delaware` -rlppueiuen neeember 23,1943, senat No. 515,367

(ci. 12s-ros) 11 Claims.

This invention relates to governors and refers particularly to agovernor for small portable internal combustion engines.

Heretofore it has been the custom to provide such small engines withgovernors actuated by the response of a vane'or blade located in thepath of the air blast created by the cooling ian of the engine. PatentNo. 1,660,079, issued to Perry E. Mack, February 21, 1928 is anillustration of this past form of governor.

With the advent of smaller engines and consequent restriction inavailable space, the past forms of governors have been foundunsatisfactory. This is particularly so in situations where the servicefor which the engine is used subjects encountered in the past with thesocalled wind vane type of governor.

Another object of this invention is to provide a compact and simplemechanism for utilizing centrifugal force to effect the desiredgoverning action.

In this connection it is a further object of this invention to so mountthe governor mechanism y on the engine that it is driven from one of thetiming gears of the engine.

Still another object of this invention is to insure adequate lubricationof all parts of the governor mechanism from the lubricant containedWithin the crankcase of the engine.

Small portable internal combustion engines have many uses and often itis necessary to provide means whereby the operator can quickly alter thespeed of the engine, notwithstanding the presence of the governorthereon.

It is, therefore, another object of this invention to provide meanswhereby the throttle valve of the engine may be manually adjustedwithout interference from the governor and without in anywise alteringthe adjustment of the governor.

Still another object of this invention is to provide means whereby themaximum speed for which the governor can beset may be manually adjustedat the factory and protected against un authorized tampering.

With the above and other objects in view, which vention resides in thenovel construction, combination and arrangement of parts substantiallyas hereinafter described and more particularly defined by' the appendedclaims, it being understood thatsuch changes in the precise embodimentof the hereindisclosed invention may be made as come within the scope ofthe claims.

The accompanying drawings illustrate several complete examples of thephysical embodiment of the invention constructed according to the bestmodes so far devised for the practical application of the principlesthereof, and in which:

Figure 1 is a view in side elevation with parts broken away illustratingthe application of this invention to a conventional small internalcombustion engine;

Figure 2 is an enlarged longitudinal sectional view through the governormechanism, per se, illustrating the manner in which it is mounted on theengine to be driven by one of the engine timing gears;

Figure 3 is a perspective view of the various parts of Athe governormechanism shown separated and in their proper order of assembly;

Figure 4 is a detail sectional view of the governor mechanism andillustrating particularly the manner in which the application oflubricant to a remote part of the mechanism is assured;

Figure 5 illustrates a means for setting the adjustment of the governorwhich is slightly modified from that shown in Figures 1 and 2;

Figure 6 illustrates another modification i'n `this respect;

Figure 7 is a detail fragmentary view showing' ing drawings, in whichlike numerals indicate like parts, the numeral 5 designates thecrankcase of a small portable internal combustion engine of conventionaldesign and construction As is customary, the engine is equipped with acarburetor 6 and timing gears l, only one of which is illustrated. Thecarburetor has the usual throttle valve 8, the shaft 9 of which has willappear as the description proceeds, this ina lever Il! secured theretoto provide means by whlch the valve may be adjusted.

The governor, indicated generally by the numeral II, ls entirelymechanical and is mounted on the side of the crankcase between it andthe carburetor so as to be closely adjacent to the throttle valve leverI0.

The crankcase has a hollow protuberance I2 projecting from the side wallthereof at a point adjacent to the timing gear 1 so that said gear isaccessible from inside the hollow protuberance.

This hollow protuberance has an open face I3 substantially parallel withthe plane of the timing gears.

Fixed in the closed end wall I 4 of the hollow protuberance is a stubshaft I5. This shaft projects toward the open face I3 and freelyrotatably mounts a gear I6, the teeth of which mesh with the timing gearl. The gear I5 is preferably a die casting and has a stem Il' integraltherewith and projecting axially therefrom.

A longitudinal slot i8 extending diametrically through the stem providesfor the reception of the attaching arms IS of a pair of fly-balls 20.The arms i9 are right angular and have their end portions which arereceived in the slot I8 of such size that when the fly-balls are intheir retracted positions, the end portions of the arms lie whollywithin the confines of the stem, while the actual fly-balls, which arebut enlargements on the outer ends of the arms, occupy a positionadjacent to the gear I6.

A single pivot pin 2l connects the arms of the two fly-balls to the stemat a, point near the outer end thereof so that the y-balls swingoutwardly away from the gear in response to centrifugal force.

This outward swinging motion of the y-balls is transmitted to a flangedcup 22 slidable on the stem I'I. The flange 23 of the cup bears againstthe fly-balls and its outer closed end 2d is substantially pointed tohave restricted contact with a lever 25.

The lever is xed to the inner end of a short shaft 25 journalled in abushing 2l. The bushing 21 is threaded into an aperture formed in acover 28 secured to the open face of the protuberance. .The outer end ofthe shaft 26 has an arm 29 secured thereto which in turn is connected tothe lever .Ill through a link 3D.

A tension spring 3| hooked into one of a. series of holes 32 in the arm29 and to an anchor 33 yieldingly urges the lever 25 against the pointedend of the cup 22 and tends to hold the parts in a position at which thethrottle valve is fully open.

During operation it will be apparent that theresponse of the fly-ballsto centrifugal force pushing on the flange 23 forces the cup 22outwardly along the stem Il. This movement is opposed by the tension ofthe spring 3| which at all times acts to press the lever 25 against thepointed end of the cup. Thus, with a proper balance between the springtension and centrifugal force, the desired regulation of the throttlevalve is achieved.

The hole of the arm 29 into which the spring 3I is hooked, of course,provides a measure of the spring tension and thus through properselection of the point of application of the spring a wide range ofconditions is accommodated.

Attention is directed to the simplicity with which the assembly of thegovernor mechanism ins effected. The stub shaft I5 upon which the diecast gear I6 is journalled is driven into position in the back wallI4'of the'hollow protuberance. The dies cast gear with the fly-balls andcup 22 assembled thereon slipped through the open face of theprotuberance and onto the stub shaft I5.

The cover 28, which preferably is also a die casting, has the shaft 26with its lever 25 and arm 29 easily assembled therewith, and thissubassembly is readily applied to the open face of the protuberance tocomplete the assembly.

Referring to Figure 2 it will be noted that the governor drive gears 1and I6 are helical and that the helix angle of the teeth is such as torequire the governor gear I6 to be driven in a clockwise direction asviewed from the open face I3 of the protuberance I2. Hence, the governorgear I6 is thrust toward the bottom of the protuberance I2 duringoperation of the engine and consequently maintained assembled on thestub shaft The yielding pressure of the lever arm 25 against the tip ofthe cup 22 in addition to holding the cup assembled with the governor isalso transmitted through the flange of the cup andthe fly-balls 2li tothe governor gear I6 to assist in holding the parts operativelyassembled.

To accommodate the cup 22 the cover 28 has a cavity 34 opening to theinterior of the hollow protuberance when the cover is in position and asclearly shown in Figure 2, the free end of the lever 25 operates in thebottom of this cavity.

Inasmuch as the interior of the hollow protuberance is in directcommunication with the inside of the crankcase, adequate lubrication forthe governor mechanism is assured. Most of the mechanism receiveslubrication directly from the oil splashed into the protuberance so thatno special provision need be made for its lubrication.

However, it was found that the point of contact between the lever 25 andthe end of the cup 22 was not adequately lubricated by the Oil splashedinto the protuberance. To insure lubrication of this vital wear point aprojection 35 is formed on the cover 28 to extend to a point closelyadjacent to the periphery of the gear I6 and a passageway 36 leads fromthe base of this projection back through the cover to a point close tothe lever 25.

Hence, as clearly shown in Figure 4, lubricant splashed on" the gear I6accumulates on the projection 35 and flows back to the lever 25 to keepits contact with the cup 22 adequately lubricated.

In addition to the adjustment afforded by changing the series of holesin the arm 29 into any one of which the spring 3I may be hooked, it isalso possible to adjust the setting of the governor by altering thelocation of the anchor 33. To this end the anchor 33 is on the outer endof a medially pivoted lever 37, the other end of which has an adjustingrod 38 connected thereto. This rod extends up to the top of the engineand passes through a supporting arm 39. Its upper extremity is threadedto receive a nut member 40 which bears on the supporting arm 39. Hence,tightening and loosening the nut member raises and lowers the rod 38 toeffect a corresponding adjustment of the anchor 33, a spring lil beingprovided to hold the nut in any adjusted position.

vTo guard against adjusting the governor setting beyond the point atwhich the engine speed is safe, a speed limiting screw 42 is provided.This screw is threaded into a projection on the lever 31 and isengageable with a fixed abutment 43 to limit the extent to which thetension of the spring 39 can be increased. If desired, this screw may besealed at the factory by solder or the like.

To further safeguard the adjustment, a guard M is fastened over theparts by which adjustment is effected.` This guard is convenientlymounted by screws threaded into a tapped hole 45` in the pivot studwhich mounts the lever 31 and by a screw threaded into a tapped hole inan ear 46 integral with the cover 28. The screws by which the guard isheld in place are, of course, desirably sealed against unauthorizedremoval.

In place of the screw adjustment adorded by the nut 40 a pivoted handlever 41 may be provided as illustrated in Figure 5. This lever isconnected to th'e rod 38 as at 48 so that adjustment thereof raises andlowers the arm. In addition to being directly actuated, the lever 41 maybe driven from a remote point through a flexible wire 49 in the usualmanner.

Still another manner of adjusting the position of the spring anchor 33is illustrated in Figure 6. As there i sh'own, a speed adjusting screw50 threads into an arm 5I conveniently secured in fixed position on theengine by the same stud which pivotally mounts the lever 31. An ear 52which reaches around the side of the crankcase is formed on the arm 5ito hold th'e same against swinging about its mounting screw. The speedadjusting screw 50 is accessible by means of a long handled screwdriver,and as before the speed limiting screw 42 may be lprovided to limit themaximum speed for which the governor can be set.

In cases where unauthorized tampering with the governor adjustment isnot a factor and where the engine is not operatedunder circumstancesresulting in extreme vibration, th'e simple method of holding the lever31 in set position, shown in Figure 1, may be employed. As here shown, afriction spring 53 is merely provided between the head 54 of the screwstud about which the lever 31 pivots so that the spring bearsfrictionally against th'e face of the lever and thereby holds the samein set position.

In some cases it may be desirable to provide means for manuallyactuating" the throttle without altering or affecting the adjustment ofthe governor or its ability to maintain a predetermined engine speed.For this purpose the construction illustrated in Figures 8 and 9 isprovided. As here shown, the shaft 9 of the throttle valve has an arm 55fixed thereto preferably Yat the end of the shaft opposite that at whichthe lever i is located.

Freely rotatably mounted on th'e shaft outwardly of the arm 55 is a disc56. On the inner face of this disc an abutment 51 projects rearwardlyinto the path oan abutment 58 on the arm 55 so that upon rotation of thedisc 56 in a counterclockwise direction, as viewed in Figure 8, theabutments 51 and 58 can be brought into engagement to thereby permit the`application of turning force onto the throttle valve sh'aft.

This force may be applied by directly grasping the disc, or as shown inFigures 8 and 9, a flexible wire may be hooked into one of a pluralityof holes t@ in the disc. In view of the multiplicity of the holes Bil,it is possible to havethe flexible wire approach the disc from anyangle. Thus, any installation can be readily accommodated.

The advantage of this attachment is that it enables the operation, forinstance of a cycle, to control the throttle as desired as long as theengine speed is below that for which the governor is set.

From the foregoing description, taken in connection with' theaccompanying drawings, it Will be readily apparent to those skilled inthe art that this invention provides an exceedingly simple and practicalgovernor especially adapted for small internal combustion engines wherespace is at a premium; and that by virtue of its particu lar design theapplication of the governor to an engine of this type is a simplematter.

What I claim as my invention is:

1. A governor for controlling the throttle valve of a combustion enginehaving a crankcase provided with a boss for mounting th'e governor.comprising: a helical gear adapted to be driven from an engine gear; ajournal stud for rotatably mounting the helical gear from the mountingboss, the direction of rotation of the gear and the-helix inclinationbeing chosen so that the helical gear is thrust against th'e mountingboss; a cylindrical stem on the helical gear extending axially therefromin the opposite direction from the journal stud; overlapping bell-cranklevers pivoted within the st'em and having weighted ends spaced radiallyfrom the stem axis and normally lying against the face of the helicalgeanall other parts of the bell-crank levers being at all Itimesenclosed within the cylindrical bounding surface of the stem; and aflanged cylindrical cup fitting on the stem with its ange engaged withthe weighted endsof the levers whereby outward movement of the weightsslidingly displaces the cup along the stem to provide the source ofmotion necessary nal stud; overlapping bell-crank levers pivoted withinthe stem and having weighted ends spaced radially from the axis of thestem and normally lying directly adjacent to the face of the gear, allother parts of the bell-crank levers being at all times enclosed within.the `cylindrical bounding surface of the stem; and a anged cylindricalcup ntting on the stem with its flange engaged with the Weighted endsofthe levers whereby outward movement of the weights slidingly displacesthe cup along the stem to provide a source of motion necessary for thecontrol of the throttle valve.

3. A governor for controlling the throttle valve of a combustion engine,said engine having a stud provided for mounting 1 the governor thereon,

comprising: a gear journalled on said stud; a cylindrical stem on thegear extending axiallytherefrom in the opposite direction from thejournal stud; overlapping bell-crank levers pivoted within the stem andhaving weighted ends spaced radially from the stem axis and normallylying closely adjacent to the face of the gear, all other parts i of thebell-crank levers being enclosed Withingthe cylindrical bounding surfaceof the stem; a flanged cylindrical cup fitting on the stem with its angeengaged with the Weighted ends of the levers whereby outward movement ofthe weights slidingly displaces the cup along the stem, the end of thecup enclosing the end of the stem; a cover for enclosing the stem andcup; and means guided in the cover for engagement by the cup fortransmitting displacement of the cup to the valve to be governed.

4. A governor for controlling the throttle valve of a combustion engine,said engine having a stud provided for mounting the governor thereon,comprising: a gear journalled on said stud; a cylindrical stem on thegear extending axially therefrom in the opposite direction from thejournal stud; overlapping bell-crank levers pivoted within the stem andhaving weighted ends spaced radially from the stem axis and normallylying closely adjacent to the face of the gear, all other parts of thebell-crank levers being at all times enclosed within thev cylindricalbounding surface of the stem; a fianged cylindrical cup fitting on thestem with its iiange engaged by the weighted ends of the levers wherebyoutward movement of the weights in response to centrifugal forceslidingly displaces the cup along the stem, the end of the cup extendingaround the end of the stem to enclose the same; a cover for enclosingthe stem and cup; and a lever pivoted in the cover with one of its armsin the path of the end of the cup and providing for regulation of thethrottle valve during operation of the gov 5. A governor for an internalcombustion engine having a throttle valve yieldingly urged to openposition by a spring, said governor comprising: a rotatable memberprojectible into an opening in the engine crankcase to be driven by arotating part therein; centrifugally responsive means carried by saidrotatable driven member and movable outwardly thereof in response tocentrifugal force; a cover for sealing the opening in the enginecrankcase and for enclosing the governor parts; an arm pivotally carriedby the cover at the interior thereof and adapted to have a motiontransmitting connection with the throttle valve so as to effectadjustment thereof toward closed position against its spring; meansinside the cover maintained engaged between said centrifugallyresponsive means and said arm by the action of the valve spring on saidarm for tra'nslating outward movement of the centrifugally responsivemeans into valve closing motion of said arm; and means on the interiorof the cover for collecting oil issuing from said crankcase opening andfor leading such oil to the point of engagement between the arm and saidtranslating means.

6. A governor for an internal combustion engine having a throttle valveyieldingly urged to open position by a spring, said governor comprising:a gear projectible into an opening in the engine crankcase to be drivenby an engine gear therein; a stem on said gear projecting outwardlythrough the opening of the crankcase; weighted levers pivotally carriedby said stem for outward motion away from the axis of the stem inresponse to centrifugal force; a flanged cup slidable on said stem andhaving its flange adjacent to the weights of the levers whereby outwardmovement of the levers in response to centrifugal force slidinglydisplaces the cup along the stem; a cover for sealing the opening in thecrankcase and for enclosing the governor parts; a lever pivotallycarried by thecover and having an arm disposed at the interior thereofto lie in the path of sliding movement of said flanged cup, said leverbeing adapted for connection with the throttle valve to control the samewhereby the lever is influenced by the throttle spring in a manner suchas to cause said arm of the lever to exertY an axial force on the cupopposite to that imparted to the cup by the Weights during movementthereof in response to centrifugal force; and means on the interior ofthe cover for collecting oil issuing from said crankcase opening and forleading such oil to the point of engagement between the arm and cup soas to minimize wear at said point.

7. Manual control means for adjusting the throttle shaft of anautomatically governed com-4 bustion engine wherein the governorconnection to the throttle shaft includes a governor lever and a springacting on the lever and the throttle shaft in a direction tending tomaintain the shaft in a valve open position. comprising: an abutment xedto the throttle shaft; a disc having a series of holes about its edgefor adjustable connection to remote control means, said disc beingloosely journalled on the throttle shaft; and an abutment on the discprojecting into the plane of the shaft carried abutment to provide fortransmission of rotation from the disc to the throttle shaftindependently of automatic adjustment of the throttle shaft by thegovernor.

8. In a governor for internal combustion engines having timer gears anda throttle valve: a gear adapted to be driven by one of said timinggears; a relatively short axial stem integral with the gear andprojecting from one face thereof; a pair of ily-balls havingsubstantially right angular shaped arms each having an end portionthereof nested into a common slot in said stem; a common pivot near theend of the stem joining the extremities of said end portions of the armsto the stem so that the fly-balls swing outwardly away from the gear inresponse to centrifugal force; a cupslidable on said stem having aflange at its open end engaging the ilyballs whereby response of theiiy-balls to centrifugal force slides the cup axially along the stem,said cup having its closed end extending around the end of the stem; andmeans engaged by the closed end of the cup so as to be actuated by thecup during sliding motion thereof along the stem providing a source ofmotion necessary for the control of the throttle valve.

9. In a governor for small internal combustion engines having an openfaced protuberance on the crankcase thereof, the face of which issubstantially normal to the adjacent wall of the .crankcase, thegovernor including a part slidably mounted inside the protuberance tomove toward and from its open face and centrifugally responsive meansdriven from a rotating part of the engine for moving said part outwardlytoward the open face of the protuberance: a cover for the open face ofthe protuberance having a cavity to receive the end portion of saidslidable part; a tapped hole in the cover, the axis of which is parallelwith the face of the cover; a bushing threaded into said hole; a shaftjournalled in said bushing with its inner end projecting into the cavityand its outerl end outside the cover and adapted for connection to thethrottle valve of the engine; a lever arm fixed to the inner end of theshaft and engaging the end of said part; and a spring acting on saidshaft in a direction such that the lever arm is held against said part.

10. In an internal combustion engine having a throttle valve to beautomatically and manually controlled: a governor includingcentrifugally responsive iiy-balls anda part actuated by response ofsaid fly-balls to centrifugal force; a pivoted arm connected'with saidpart; a spring acting on the arm and applying force thereon in adirection to maintain the same drivingly connected with said part tothereby oppose centrifugal force acting on said fly-balls, said armbeing adapted `to have a motion transmitting, connection with thethrottle valve; an adjustable spring anchor for increasing anddecreasing the spring force applied to the arm to thereby determine theengine speed to be maintained by the governor; a pivot for the springanchor providing for angular adjustment thereof, said amm pivotincluding friction retaining means for holding the anchor againstaccidental angular adjusting motion; a stop on the spring anchor tolimit increase in spring force, said stop being adjustable to apredetermined engine speed limit: and a remote control arm providing formanual adjustment o! the angular position of said spring anchor.

11. In a governor for internal combustion Aeng'ines having an open facedprotuberance on the crankcase thereof communicating with the inside ofthe crankcase, the open face of which is substantially normal to theadjacent wall on the crankcase, said governor having a part slidablymounted inside the protuberance to move toward and from its open faceand centrifugally responsive means driven from a rotating partv of theengine for moving said part outwardly toward the open face of theprotuberance, the open communication of the interior of the protuberancewith the inside of the crankcase ailording lubrication for saiddesignated parte by lubricanta splashed into the' protuberance: a coverfor the open taceof the protuberance having a cavity to receive the endportion ot the slidably mounted governor part; a lever pivotally mountedon the cover with its i'ree end in the cavity and engaging the end ofsaid slidably mounted governor part; an arm on the outside of the coverconnected with said lever to move in unison therewith, said arm beingconnectible with the throttle valve of the enginefto control the same; aspring connected with said arm and applying a force thereon to hold thelever against said slidably mounted governor part; and means forassuring the presencef lubricant at the juncture of said lever and theslidably mounted governor part comprising a projection on the coverextending into the hollow protuberance to have lubricant depositedthereon, and a passageway leading from the base of the projection to aa0 point adjacent to the juncture oi the lever and slldably mountedgovernor part.

WERNER E. ARMSTRONG.

